Backgrond:
I am creating a Login
component.
saga.js
is composed by 3 functions
1. rootSaga
. It will execute the list of sagas
inside
2. watchSubmitBtn
. It will watch the click on the submit button and dispatch an action.
3. shootApiTokenAuth
will receive dispatched action
and process axios.post
the return value is promise
object
In action:
Backend returns 400
to the React
. This case no problem I can read the payload
and display in the render()
easily. But when 200
is returned.
I need to let user go to the url /companies
.
Attempt:
I had tried put this.props.history.push('/companies');
in the componentWillUpdate()
, but it does not work. I have to click Submit
2 times to get React understand that token
has been saved.
Login.js
import React, {Component} from 'react';
import ErrorMessage from "../ErrorMessage";
import {Field, reduxForm} from 'redux-form';
import {connect} from 'react-redux';
import {validate} from '../validate';
import {SUBMIT_USERNAME_PASSWORD} from "../../constants";
class Login extends Component {
constructor(props) {
//Login is stateful component, but finally action will change
//reducer state
super(props);
const token = localStorage.getItem('token');
const isAuthenticated = !((token === undefined) | (token === null));
this.state = {
token,
isAuthenticated,
message: null,
statusCode: null
};
}
onSubmit(values) {
const {userid, password} = values;
const data = {
username: userid,
password
};
this.props.onSubmitClick(data);
}
componentWillUpdate(){
console.log('componentWillUpdate');
if(this.props.isAuthenticated){
this.props.history.push('/companies');
}
}
renderField(field) {
const {meta: {touched, error}} = field;
const className = `'form-group' ${touched && error ? 'has-danger' : ''}`;
console.log('renderField');
return (
<div className={className}>
<label>{field.label}</label>
<input
className="form-control"
type={field.type}
placeholder={field.placeholder}
{...field.input}
/>
<div className="text-help">
{touched ? error : ''}
</div>
</div>
);
}
render() {
const {handleSubmit} = this.props;
return (
<div>
<ErrorMessage
isAuthenticated={this.props.isAuthenticated}
message={this.props.message}
/>
<form onSubmit={handleSubmit(this.onSubmit.bind(this))}>
<Field
name="userid"
component={this.renderField}
placeholder="User ID"
type="text"
/>
<Field
name="password"
component={this.renderField}
placeholder="Password"
type="password"
/>
<button type="submit" className="btn btn-primary">Submit</button>
</form>
<a className='btn btn-primary' href="https://www.magicboxasia.com/">Sign up</a>
</div>
);
}
}
const onSubmitClick = ({username, password}) => {
return {
type: SUBMIT_USERNAME_PASSWORD,
payload: {username, password}
};
};
const mapStateToProps = (state, ownProps) => {
return {
...state.login
}
};
export default reduxForm({
validate,
form: 'LoginForm'
})(
connect(mapStateToProps, {onSubmitClick})(Login)
);
saga.ja
const shootApiTokenAuth = (values) =>{
const {username, password} = values;
return axios.post(`${ROOT_URL}/api-token-auth/`,
{username, password});
};
function* shootAPI(action){
try{
const res = yield call(shootApiTokenAuth, action.payload);
yield put({
type: REQUEST_SUCCESS,
payload: res
});
}catch(err){
yield put({
type: REQUEST_FAILED,
payload: err
});
}
}
function * watchSubmitBtn(){
yield takeEvery(SUBMIT_USERNAME_PASSWORD, shootAPI);
}
// single entry point to start all Sagas at once
export default function* rootSaga() {
yield all([
watchSubmitBtn()
])
}
Problem:
How can I set the component state and push
to url /companies
? after backend returns 200
?
I usually handle conditional navigation like that in the saga.
The simplest answer with the existing code is to pass a history object as a prop in the SUBMIT_USERNAME_PASSWORD action and do the history.push() call in the success case of the saga, something like:
const onSubmitClick = ({username, password}) => {
const { history } = this.props;
return {
type: SUBMIT_USERNAME_PASSWORD,
payload: {username, password, history}
};
};
.......
function* shootAPI(action){
try{
const res = yield call(shootApiTokenAuth, action.payload);
const { history } = action.payload;
yield put({
type: REQUEST_SUCCESS,
payload: res
});
history.push('/companies');
}catch(err){
yield put({
type: REQUEST_FAILED,
payload: err
});
}
}
I am not as experienced in react but you could achieve it as follows:
1.Create a new Module: history-wrapper.ts
export class HistoryWrapper {
static history;
static init(history){
HistoryWrapper.history = history;
}
}
2.In you login.jsx
HistoryWrapper.init(history);//initialize history in HistoryWrapper
3.Subsequently anywhere in your app
HistoryWrapper.history.push('/whatever');
React has additional lifecycle. I just know it today. They are many of them.
componentDidUpdate() {
this.props.history.push('/companies');
}
yield put(push('/path-to-go'));
solved my problem
来源:https://stackoverflow.com/questions/47864755/redux-saga-and-history-push